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Where can it possible to find pictures or drawings of "endplate"? (for "winglet" is much easier, but not endplate)

I'm asking what's written above, after I read the following text from Raymer and I need a better comprehension of it.

The wing aspect ratio "$A$" is the geometric aspect ratio of the complete reference planform. the effective aspect ratio will be increased by wing endplates or winglets

Endplate: $A_{effective} = A(1+1.9\frac{h}{b})$ - (12.10) where $h$ = endplate height

Winglet: $A_{effective} = \approx 1.2A$ - (12.11)

These effective aspect ratios should also be used in the induced drag calculations below. note that Eq. (12.11) for winglets is a crude approximation based upon limited data for wings of moderate aspect ratio

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The extra drag due to non-elliptical lift distribution and the flow separation can be accounted for using e, the "Oswald span efficiency factor". This effectively reduces the aspect ratio, producing the following equation for $K$

$K=\frac{1}{πAe}$ (12.48)

If the wing has end-plates or winglets, the effective aspect ratio from Eq. (12.10) or (12.11) should be used in Eq. (12.48)

(Source: Daniel P. Raymer "Aircraft design . A conceptual approach" , Chapter 12 Aerodynamics)

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  • $\begingroup$ The endplate that i think the OP is referring to is the the part that maintenance attaches to the wing to cover the end of the wing when a wingtip is removed, due to damage for example. $\endgroup$ – J Walters Apr 7 '16 at 11:05
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I seem to remember that wing end plates were sometimes used on Short Take Off and Landing(STOL) aircraft in the 1960's.

I found a few photos while doing an internet search but they seem to be much more prevalent on race car wings these days.

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Here is an explanation of why end plates are used on race cars: Analysis: Rear Wing Endplates

The endplate has two functions, the primary reason for their shape is to control the wingtip vortices at the trailing edge of the wing as this reduces drag and also lift. The second reason is that they control how the airflow makes its way over, under or around the aerofoil device that is creating the downforce on the car, resulting in better airflow management and maximising the performance of the component.

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